1839.] WET AND DRY SEASONS. 233 



from rusting; and the exposed surfaces of the rocks along the 

 coast are coated over with the oxide of iron. 



Periods, or cycles, often or twelve years duration, distinctly 

 mark the division of the Australian climate into wet and 

 dry. In the course of each cycle, there is ordinarily one year 

 of unmitigated drought, during which no rain falls, whose ef- 

 fects are visible, as well in the mountains and fells of the ele- 

 vated regions, as in the boggy marshes and desert flats of the 

 interior — as well in the sandy plains along the southern coast, 

 as in the jungles of tropical Australia. This dry season is 

 followed by a year of freshets and floods : the rains are then 

 incessant, but they diminish in number and quantity, in each 

 succeeding year, until the dry epoch again recurs. It is only 

 in the years intervening between these two extremes, that 

 the regular transitions from one season to another, before 

 hinted at, are observable. 



Dews are abundant at all seasons, and especially so in the 

 .summer, and during the long droughts. Earthquakes are 

 not common except on the northern coast, where they are oc- 

 casionally felt, Hail storms often occur, and thunder and 

 Iisrhtninff are likewise frequent. Sometimes a brilliant dis- 

 play of the most vivid electricity may be witnessed for a suc- 

 cession of days, — flash following close upon flash, with but 

 brief intermissions, and unaccompanied by either thunder or 

 rain. In the sandy districts a singular phenomenon is often 

 witnessed. Tall columns of dust, or whirlwinds, twenty feet 

 broad, and from seventy to one hundred feet high, may be 

 seen moving along in stately procession, striding majestically, 

 like giant spirits, over brook and plain, with the speed of a 

 race horse. At Sydney, these dust winds, or " brick-field- 

 ers," as they are called, are a great source of annoyance; 

 and though doors and windows are always carefully closed 

 when they are seen approaching, everything in the house 

 is sure to be covered with the thick, fine powder, which pene- 

 trates through the smallest crevice. 



Were this not a country of singularities, the inference fairly 

 deducible from the facts which have been detailed, would be, 



